Sophisticated, critical electronic systems require power supplies having the attributes of very high quality and reliability. These attributes are not always available from the power supplied through typical utility organizations. Unforeseen natural events, such as storms, earthquakes or other natural disasters can unexpectedly disrupt the normal flow of electricity to installations such as computing complexes (i.e., information technology data centers). Power interruptions may also occur from man-made occurrences. A recent, large-scale failure of a major portion of the power grid in the Northeastern portion of the United States underscores the vulnerability of computing complexes to massive power disruptions, both natural and man-made.
Uninterruptible Power Supply (UPS) systems are power conversion systems that are commonly used to provide conditioned, reliable power for devices and systems such as computing complexes, telecommunications networks, medical equipment and the like. UPS systems can provide temporary power to the devices and systems within such complexes so that the devices and systems can continue to operate despite the loss of the primary power source and thereby can reduce the likelihood that valuable data may be lost.
UPS systems may provide uninterrupted power by switching from a primary power source (e.g., electrical utility supplied power) to a secondary power source (e.g., UPS supplied battery power) if loss of the primary power source is detected. When the primary power source is restored, the UPS system may switch from the secondary power source back to the primary power source. Similarly, the UPS system may switch from the primary power source to the secondary power source if the UPS system determines that the primary power source is inappropriate. For example, if a voltage level of the primary power source is less than a minimum acceptable level, the UPS system may provide uninterrupted power by switching from the primary power source to the secondary power source.
While UPS systems provide a temporary solution to the loss of primary/conventional power (e.g., utility generated power) within a computing complex, the amount of battery power available from UPS systems is finite. Thus, if a disruption occurs to the conventional power source, the IT administrator is faced with a decision as to when (or even if) to power down devices within the computing complex.
If the IT administrator shuts down all computing resources as soon as the UPS goes on battery, the administrator protects the systems and their associated storage devices from damage and data loss, but risks significant downtime to critical systems/devices if the conventional power source is quickly restored. If the IT administrator waits to shut down all systems/devices within the computing complex only after a low battery alarm is received from the UPS, the administrator keeps critical systems/devices up for a longer period of time, but risks not being able to successfully power down all systems/devices within the computing complex before the UPS battery is exhausted. In another instance, the IT administrator may have high confidence that the conventional power resource will be restored before the UPS battery is exhausted, and choose to not power down any systems/devices within the computing complex. In this instance, the administrator risks a severe loss of data/equipment if the UPS battery completely drains before conventional power is restored.
There is a need for an automated method to manage the selected shutdown of devices within an information technology computing complex when the loss of conventional utility service occurs. Such a method should selectively shutdown systems/devices within the computing complex based on the criticality of the systems/devices and the current state of backup power resources available within the computing complex.